January 28, 1892] 



NATURE 



507 



pearance of the line of demarcation between organic and in- 

 organic compounds; for here we derive what may truly be 

 considered as an inorganic compound from a substance so purely 

 oi^anic as an ethereal salt. 



In our chemical note of last week the experiments of Dr. Merz 

 upon magnesium nitride, MgjNj, were described. It will be 

 remembered that magnesium was shown to combine with 

 nitrogen in a most vigorous manner when heated to redness 

 in a stream of the gas. M. Ouvrard, in the current number of 

 the Comptes rendtis, shows that lithium too combines ener- 

 getically with nitrogen. A quantity of this metal was placed 

 in a small boat constructed of iron, the only convenient sub- 

 stance which will withstand the action of fused lithium, and 

 the boat was placed in a combustion tube through which a 

 stream of nitrogen was driven. Upon gradually raising the 

 temperature of the lube and contents, a point was attained, in 

 the neighbourhood of low-redness, when combination suddenly 

 occurred, the metal becoming brilliantly incandescent and in- 

 creasing rapidly in volume, while the nitrogen in the apparatus 

 was almost entirely absorbed. On continuing the stream of 

 nitrogen until the apparatus became quite cold, the lithium 

 nitride was found in the form of a black spongy mass. Its 

 composition was proved by analysis to be LigN, analogous to 

 magnesium nitride, Mg3N2, and to ammonia, H3N. Indeed, it 

 may readily be converted into the latter gas by heating it in a 

 stream of hydrogen. It behaves with water very similarly to 

 magnesium nitride, at once decomposing that liquid with 

 liberation of large quantities of ammonia and formation of a 

 solution of lithia. 



The additions to the Zoological Society's Gardens during the 

 past week include two Macaque Monkeys [Macacus cynomolgiis 

 6 ? ) from India, presented respectively by Mr. B. H. Heald 

 and Mrs. E. Day ; a Rhesus Monkey {Macacus rhesus) from 

 India, presented by Mr. Alfred J. Hayward ; two Common 

 Squirrels {Sciurus vulgaris), British, presented by Master Fred 

 Corfield ; two Ring-necked Parrakeets {Palceornis torquatus) 

 from India, presented by Miss Heinekey ; six Mantell's Apteryx 

 {Apteryx mantelli) from New Zealand, deposited. 



OUR ASTRONOMICAL COLUMN. 



Wolf's Numbers for i^^i.— Comptes rendus for January 

 18 contains a communication by M. Rodolf Wolf on the state of 

 solar activity in 1891. The following table shows the results 

 of solar observations made at Zurich Observatory, and magnetic 

 observaiions made at Milan. The relative numbers {r) have 

 been obtained by the method used in previous years. 



A New Journal.— The Sidereal Messenger has ceased to 

 exist under this title, and has merged into Astronomy and 

 Astro- Physics. The first copy of this new journal has recently 

 been published in America. Its production is the natural result 

 of the development of astronomical physics. One portion of 

 the journal is to be devoted to general astronomy, whilst the 

 other deals with astro-physics. The editor of the former is Mr. 

 W. W. Payne, who so ably conducted the Sidereal Messenger, 

 and the latter section is under the charge of Prof. G. E. Hale, 

 whose excellent works on solar prominence photography are 

 j known to all spectroscopists. If the editors can fill future 

 I numbers of the journal with so many interesting and important 

 articles and notes as make up the first number, they will attain 

 a well-deserved success. Many of the articles have been pub- 

 lished in other journals, but this, of course, does not in the least 

 detract from the value of the new journal. The literature of 

 spectroscopy is truly said to be widely scattered, and Prof. Hale 

 is doing a meritorious work in bringing it all together. 



Means... 35-6 ... 28*8 ... 7-77 ... 1-22 



The relative numbers and the magnetic variations show a 

 decided increase on the values obtained for 1890, and the 

 parallelism between the two series continues as in former 

 years, A discussion of these and previous results indicates that 

 the last minimum of solar activity has the date 1889-6, 



NO. 116 1, VOL. 45] 



KOREA. 



A T the meeting of the Royal Geographical Society on Mon- 



■^^ day night, the paper read was on a journey through North 



Korea to the Ch'ang-pai Shan, by Mr. Charles W. Campbell. 



I Ch'ang-pai Shan, or " Ever White Mountain," is the same as 



I Peik-lu San, or White Head Mountain, and " The Long White 



i Mountain," so graphically described by Mr. James in his book 



i of that title. It lies in Manchuria, just beyond the Korean 



boundary, and is remarkable for the deep-blue lake which lies 



in a deep hollow on the ridge joining two of its peaks. It was 



not till August 1889 that Mr, Campbell succeeded in leaving 



Seoul, the capital of Korea. He journeyed east and north 



along the coast. The country traversed is typical of the centre 



and north of the country. 



"Korea," Mr. Campbell said, "is a land of mountains. 

 Go where you will, a stretch of level road is rare, and a stretch 

 of level plain rarer still. The view from any prominent height 

 is always the same ; the eye ranges over an expanse of hiil-tops, 

 now running in a succession of long billowy lines, now broken 

 up like the wavelets in a choppy sea, often green with forest, 

 but just as often bare, brown, and forbidding. Clear mountain 

 brooks or shallow streams rushing over beds of gravel are never 

 wanting in the valleys below, where a rude log bridge, or curling 

 smoke, or the presence of cultivation, leads you to observe the 

 brown thatch of some huts clustered under the lea of a hill. 

 These hamlets are of two distinct kinds — the purely agricul- 

 tural, and those which depend as much on the entertainment of 

 travellers as on farming. The site of the agricultural village is 

 a hill-slope facing the south. Over this, low, mud-walled, 

 straw-thatched hovels, each standing in its own patch of garden, 

 which is protected by a neat fence of interlaced stems, are scat- 

 tered at random, and there is not much attempt at a street any- 

 where. Every house has its threshing-floor of beaten clay, the 

 workshop of the family. The stream which runs past the foot 

 of the hill, or courses down a gully in its side, is lined with 

 women and girls washing clothes with sticks instead of soap, 

 preparing cabbages for pickle, or steeping hemp. Seen from a 

 distance, these places are quite picturesque. The uneven ter- 

 races of thatch are brightened by the foliage and flowers of 

 gourds and melons which climb all over the huts. In the gar- 

 dens surrounding each house are plots of red chilli, rows of 

 castor-oil plants, and fruit trees, such as peach, apricot, pear, 

 and persimmon. 



" The roadside village, on the other hand, is generally a most 

 unlovely spot. The only street is the main highway, which is 

 lined on both sides by a straggling collection of the huts I have 

 mentioned. Heaps of refuse, open drains, malodorous pools, 

 stacks of brushwood for fuel, nude suntanned children disport- 

 ing themselves, men and women threshing grain, and occasion- 

 ally a crowd of disputants, all combine to make it a very indifferent 

 thoroughfare. Most of the houses are inns or eating-shops. 

 The main gate of the inn leads directly from the street into a 

 quadrangle bounded on two sides by open sheds, which are 

 provided with troughs for the feeding of pack animals, and on 

 the other two sides by the guest rooms and kitchen. The 

 courtyard is untidy, often dominated by a powerful pig-stye, and 

 littered with fodder or earthenware pitchers and vats, whose 

 contents are usually the strong-smelling pickled cabbages and 

 turnips so dear to Korean stomachs. 



"The main industry, of course, is agriculture, carried on under 



